package com.earl.common.config;

import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 解决json跨域的过滤器
 *
 * @author Think
 */

@Order(Ordered.HIGHEST_PRECEDENCE)
public class BaseCorsFilter implements Filter {
    private static final String ALLOWED_HEADERS = "x-requested-with, authorization, Content-Type, Authorization, credential, X-XSRF-TOKEN, systemCode, sfcLang, hostIp, Origin, Accept, Access-Control-Request-Method,Access-Control-Request-Headers";

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {

        HttpServletResponse response = (HttpServletResponse) res;
        HttpServletRequest request = (HttpServletRequest) req;
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS, DELETE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Headers", ALLOWED_HEADERS);
        if (request.getMethod().equals(HttpMethod.OPTIONS.name())) {
            response.setStatus(HttpStatus.NO_CONTENT.value());
        } else {
            chain.doFilter(req, res);
        }
    }

    @Override
    public void init(FilterConfig filterConfig) {
    }

    @Override
    public void destroy() {
    }
}
